The IMF is concerned at the time it takes migrants to assimilate. It calculates that after five years in the country only 48 percent would likely have a job and only 60 percent after 10 years.

"Among the stock of migrants, the share of low-educated increased to about 28 percent in 2014, from 17 percent in 2005," it wrote.

However, another recent key report by banking giant Nordea estimated that Sweden's record intake of refugees could boost the country's GDP by 0.5 percent more than previously predicted next year, with those who do manage to land a job helping to plug skills gaps on the Swedish job market.

"Migration is critical for maintaining growth in the working age population which, without migration, would shrink by a cumulative three percent by 2030 and 12 percent by 2060, according to Eurostat forecasts," the IMF report agreed.

But in a country with an ageing population, "further efforts to expedite the residency permit, educational assessment, and skill validation processes, are needed in view of rising numbers," it continued.

The IMF called for looser laws concerning the hiring of less-qualified workers to offset the barrier into the labour market posed by high entry-level wages in the Scandinavian country, which proponents argue are essential to maintaining job security.

However, Finance Minister Magdalena Andersson noted in an interview with the Svenska Dagbladet newspaper in November that his promise was looking increasingly "harder to reach", with Sweden being expected to take in up to 190,000 asylum seekers over the whole of 2015.